参数资料
| 型号： | LTC3830ES8 |
| 厂商： | Linear Technology |
| 文件页数： | 13/24页 |
| 文件大小： | 0K |
| 描述： | IC REG CTRLR BUCK PWM VM 8-SOIC |
| 标准包装： | 100 |
| PWM 型： | 电压模式 |
| 输出数： | 1 |
| 频率 - 最大： | 250kHz |
| 占空比： | 95% |
| 电源电压： | 3 V ~ 8 V |
| 降压： | 是 |
| 升压： | 无 |
| 回扫： | 无 |
| 反相： | 无 |
| 倍增器： | 无 |
| 除法器： | 无 |
| Cuk： | 无 |
| 隔离： | 无 |
| 工作温度： | -40°C ~ 85°C |
| 封装/外壳： | 8-SOIC（0.154"，3.90mm 宽） |
| 包装： | 管件 |
| 产品目录页面： | 1336 (CN2011-ZH PDF) |
LTC3830/LTC3830-1
APPLICATIO S I FOR ATIO
The LTC3830/LTC3830-1 overcomes this problem by
sensing the PV CC1 voltage when G1 is high. If PV CC1 is less
than (V CC + 2.5V), the maximum G1 duty cycle is reduced
to 70% by clamping the COMP pin at 1.8V (QC in BLOCK
DIAGRAM). This increases the G2 on time and allows the
charge pump capacitor to be refreshed.
ForApplicationsusinganexternalsupplytopowerPV CC1 ,
this supply must also be higher than V CC by at least 2.5V
to insure normal operation.
For applications with a 5V or higher V IN supply, PV CC2 can
be tied to V IN if a logic level MOSFET is used. PV CC1 can be
supplied using a doubling charge pump as shown in Figure
9. This circuit provides 2V IN – V F to PV CC1 while Q1 is ON.
Figure 12 shows a typical 5V to 3.3V application using a
doubling charge pump to generate PV CC1 .
Power MOSFETs
Two N-channel power MOSFETs are required for most
LTC3830 circuits. These should be selected based
primarily on threshold voltage and on-resistance consid-
erations. Thermal dissipation is often a secondary con-
cern in high efficiency designs. The required MOSFET
threshold should be determined based on the available
an auxiliary 12V supply is available to power PV CC1 and
PV CC2 , standard MOSFETs with R DS(ON) specified at V GS
= 5V or 6V can be used with good results. The current
drawn from this supply varies with the MOSFETs used
and the LTC3830’s operating frequency, but is generally
less than 50mA.
LTC3830applicationsthatuse5VorlowerV IN voltageand
a doubling/tripling charge pump to generate PV CC1 and
PV CC2 , do not provide enough gate drive voltage to fully
enhance standard power MOSFETs. Under this condition,
the effective MOSFET R DS(ON) may be quite high, raising
the dissipation in the FETs and reducing efficiency. Logic
level FETs are the recommended choice for 5V or lower
voltage systems. Logic level FETs can be fully enhanced
with a doubler/tripling charge pump and will operate at
maximum efficiency.
After the MOSFET threshold voltage is selected, choose the
R DS(ON) based on the input voltage, the output voltage,
allowable power dissipation and maximum output current.
In a typical LTC3830 circuit, operating in continuous mode,
the average inductor current is equal to the output load
current. This current flows through either Q1 or Q2 with the
power dissipation split up according to the duty cycle:
power supply voltages and/or the complexity of the gate
drive charge pump scheme. In 3.3V input designs where
DC ( Q 1 ) =
V OUT
V IN
DC ( Q 2 ) = 1 – OUT = IN OUT
OPTIONAL
USE FOR V IN ≥ 7V
V IN
MBR0530T1
V V – V
V IN V IN
D Z
12V
1N5242
PV CC2
PV CC1
G1
0.1 μ F
Q1
The R DS(ON) required for a given conduction loss can now
be calculated by rearranging the relation P = I 2 R.
G2
Q2
L O
+
V OUT
C OUT
R DS ( ON ) Q 1 =
P MAX ( Q 1 )
DC ( Q 1 ) ? ( I LOAD ) 2
=
V IN ? P MAX ( Q 1 )
V OUT ? ( I LOAD ) 2
LTC3830
3830 F09
R DS ( ON ) Q 2 =
P MAX ( Q 2 )
DC ( Q 2 ) ? ( I LOAD ) 2
=
V IN ? P MAX ( Q 2 )
( V IN – V OUT ) ? ( I LOAD ) 2
Figure 9. Doubling Charge Pump
3830fa
13
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相关代理商/技术参数 |
参数描述 |
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| LTC3830ES8#PBF | 功能描述:IC REG CTRLR BUCK PWM VM 8-SOIC RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 切换控制器 系列:- 特色产品:LM3753/54 Scalable 2-Phase Synchronous Buck Controllers 标准包装:1 系列:PowerWise® PWM 型:电压模式 输出数:1 频率 - 最大:1MHz 占空比:81% 电源电压:4.5 V ~ 18 V 降压:是 升压:无 回扫:无 反相:无 倍增器:无 除法器:无 Cuk:无 隔离:无 工作温度:-5°C ~ 125°C 封装/外壳:32-WFQFN 裸露焊盘 包装:Digi-Reel® 产品目录页面:1303 (CN2011-ZH PDF) 其它名称:LM3754SQDKR |
| LTC3830ES8#TR | 功能描述:IC REG CTRLR BUCK PWM VM 8-SOIC RoHS:否 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 切换控制器 系列:- 标准包装:2,500 系列:- PWM 型:电流模式 输出数:1 频率 - 最大:500kHz 占空比:96% 电源电压:4 V ~ 36 V 降压:无 升压:是 回扫:无 反相:无 倍增器:无 除法器:无 Cuk:无 隔离:无 工作温度:-40°C ~ 125°C 封装/外壳:24-WQFN 裸露焊盘 包装:带卷 (TR) |
| LTC3830ES8#TRPBF | 功能描述:IC REG CTRLR BUCK PWM VM 8-SOIC RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 切换控制器 系列:- 标准包装:2,500 系列:- PWM 型:电流模式 输出数:1 频率 - 最大:500kHz 占空比:96% 电源电压:4 V ~ 36 V 降压:无 升压:是 回扫:无 反相:无 倍增器:无 除法器:无 Cuk:无 隔离:无 工作温度:-40°C ~ 125°C 封装/外壳:24-WQFN 裸露焊盘 包装:带卷 (TR) |
| LTC3831EGN | 功能描述:IC SW REG CONTROLLR SYNC 16-SSOP RoHS:否 类别:集成电路 (IC) >> PMIC - 稳压器 - 专用型 系列:- 标准包装:43 系列:- 应用:控制器，Intel VR11 输入电压:5 V ~ 12 V 输出数:1 输出电压:0.5 V ~ 1.6 V 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:48-VFQFN 裸露焊盘 供应商设备封装:48-QFN（7x7） 包装:管件 |
| LTC3831EGN#PBF | 功能描述:IC SW REG CONTROLLR SYNC 16-SSOP RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - 专用型 系列:- 标准包装:43 系列:- 应用:控制器，Intel VR11 输入电压:5 V ~ 12 V 输出数:1 输出电压:0.5 V ~ 1.6 V 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:48-VFQFN 裸露焊盘 供应商设备封装:48-QFN（7x7） 包装:管件 |
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